text: /*
   * hash algorithms used in OAuth
   *
   * Copyright 2007-2012 Robin Gareus <robin@gareus.org>
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   *
   */
  
  #if HAVE_CONFIG_H
  # include <config.h>
  #endif
  
  #if USE_BUILTIN_HASH // built-in / AVR -- TODO: check license of sha1.c
  #include <stdio.h>
  #include "oauth.h" // oauth_encode_base64
  #include "xmalloc.h"
  
  #include "sha1.c" // TODO: sha1.h ; Makefile.am: add sha1.c
  
  /* API */
  char *oauth_sign_hmac_sha1_raw (const char *m, const size_t ml, const char *k, const size_t kl) {
  	sha1nfo s;
  	sha1_initHmac(&s, (const uint8_t*) k, kl);
  	sha1_write(&s, m, ml);
  	unsigned char *digest = sha1_resultHmac(&s);
  	return oauth_encode_base64(HASH_LENGTH, digest);
  }
  
  char *oauth_sign_hmac_sha1 (const char *m, const char *k) {
  	return(oauth_sign_hmac_sha1_raw (m, strlen(m), k, strlen(k)));
  }
  
  char *oauth_body_hash_file(char *filename) {
  	size_t len=0;
  	char fb[BUFSIZ];
  	sha1nfo s;
  
  	FILE *F= fopen(filename, "r");
  
  	if (!F) return NULL;
  	sha1_init(&s);
  
  	while (!feof(F) && (len=fread(fb,sizeof(char),BUFSIZ, F))>0) {
  		sha1_write(&s, fb, len);
  	}
  	fclose(F);
  
  	unsigned char *dgst = xmalloc(HASH_LENGTH*sizeof(char)); // oauth_body_hash_encode frees the digest..
  	memcpy(dgst, sha1_result(&s), HASH_LENGTH);
  	return oauth_body_hash_encode(HASH_LENGTH, dgst);
  }
  
  char *oauth_body_hash_data(size_t length, const char *data) {
  	sha1nfo s;
  	sha1_init(&s);
  	for (;length--;) sha1_writebyte(&s, *data++);
  
  	unsigned char *dgst = xmalloc(HASH_LENGTH*sizeof(char)); // oauth_body_hash_encode frees the digest..
  	memcpy(dgst, sha1_result(&s), HASH_LENGTH);
  	return oauth_body_hash_encode(HASH_LENGTH, dgst);
  }
  
  char *oauth_sign_rsa_sha1 (const char *m, const char *k) {
  	/* NOT RSA/PK11 support */
  	return xstrdup("---RSA/PK11-is-not-supported-by-this-version-of-liboauth---");
  }
  
  int oauth_verify_rsa_sha1 (const char *m, const char *c, const char *sig) {
  	/* NOT RSA/PK11 support */
  	return -1; // mismatch , error
  }
  
  #elif defined (USE_NSS)
  /* use http://www.mozilla.org/projects/security/pki/nss/ for hash/sign */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include "xmalloc.h"
  #include "oauth.h" // oauth base64 encode fn's.
  
  // NSS includes
  #include "pk11pub.h"
  #include "nss.h"
  #include "base64.h"
  #include "keyhi.h"
  #include "cryptohi.h"
  #include "cert.h"
  
  #if 1 // work-around compiler-warning
  // see http://bugzilla.mozilla.org/show_bug.cgi?id=243245#c3
  extern CERTCertificate *
  __CERT_DecodeDERCertificate (SECItem *derSignedCert, PRBool copyDER, char *nickname);
  #endif
  
  static const char NS_CERT_HEADER[]  = "-----BEGIN CERTIFICATE-----";
  static const char NS_CERT_TRAILER[] = "-----END CERTIFICATE-----";
  static const char NS_PRIV_HEADER[]  = "-----BEGIN PRIVATE KEY-----";
  static const char NS_PRIV_TRAILER[] = "-----END PRIVATE KEY-----";
  
  void oauth_init_nss() {
  	static short nss_initialized = 0;
  	if (!nss_initialized) { NSS_NoDB_Init(NULL); nss_initialized=1;}
  }
  
  /**
   * Removes heading & trailing strings; used only internally.
   * similar to NSS-source/nss/lib/pkcs7/certread.c
   *
   * the returned string (if not NULL) needs to be freed by the caller
   */
  char *oauth_strip_pkcs(const char *txt, const char *h, const char *t) {
  	char *start, *end, *rv;
  	size_t len;
  	if ((start=strstr(txt, h))==NULL) return NULL;
  	start+=strlen(h);
  	while (*start=='\r' || *start=='\n') start++;
  	if ((end=strstr(start, t))==NULL) return NULL;
  	end--;
  	while (*end=='\r' || *end=='\n') end--;
  	len = end-start+2;
  	rv = xmalloc(len*sizeof(char));
  	memcpy(rv,start,len);
  	rv[len-1]='\0';
  	return rv;
  }
  
  char *oauth_sign_hmac_sha1 (const char *m, const char *k) {
  	return(oauth_sign_hmac_sha1_raw (m, strlen(m), k, strlen(k)));
  }
  
  char *oauth_sign_hmac_sha1_raw (const char *m, const size_t ml, const char *k, const size_t kl) {
  	PK11SlotInfo  *slot = NULL;
  	PK11SymKey    *pkey = NULL;
  	PK11Context   *context = NULL;
  	unsigned char  digest[20]; // Is there a way to tell how large the output is?
  	unsigned int   len;
  	SECStatus      s;
  	SECItem        keyItem, noParams;
  	char          *rv=NULL;
  
  	keyItem.type = siBuffer;
  	keyItem.data = (unsigned char*) k;
  	keyItem.len = kl;
  
  	noParams.type = siBuffer;
  	noParams.data = NULL;
  	noParams.len = 0;
  
  	oauth_init_nss();
  
  	slot = PK11_GetInternalKeySlot();
  	if (!slot) goto looser;
  	pkey = PK11_ImportSymKey(slot, CKM_SHA_1_HMAC, PK11_OriginUnwrap, CKA_SIGN, &keyItem, NULL);
  	if (!pkey)  goto looser;
  	context = PK11_CreateContextBySymKey(CKM_SHA_1_HMAC, CKA_SIGN, pkey, &noParams);
  	if (!context) goto looser;
  
  	s = PK11_DigestBegin(context);
  	if (s != SECSuccess) goto looser;
  	s = PK11_DigestOp(context, (unsigned char*) m, ml);
  	if (s != SECSuccess) goto looser;
  	s = PK11_DigestFinal(context, digest, &len, sizeof digest);
  	if (s != SECSuccess) goto looser;
  
  	rv=oauth_encode_base64(len, digest);
  
  looser:
  	if (context) PK11_DestroyContext(context, PR_TRUE);
  	if (pkey) PK11_FreeSymKey(pkey);
  	if (slot) PK11_FreeSlot(slot);
  	return rv;
  }
  
  char *oauth_sign_rsa_sha1 (const char *m, const char *k) {
  	PK11SlotInfo      *slot = NULL;
  	SECKEYPrivateKey  *pkey = NULL;
  	SECItem            signature;
  	SECStatus          s;
  	SECItem            der;
  	char              *rv=NULL;
  
  	char *key = oauth_strip_pkcs(k, NS_PRIV_HEADER, NS_PRIV_TRAILER);
  	if (!key) return NULL;
  
  	oauth_init_nss();
  
  	slot = PK11_GetInternalKeySlot();
  	if (!slot) goto looser;
  	s = ATOB_ConvertAsciiToItem(&der, key);
  	if (s != SECSuccess) goto looser;
  	s = PK11_ImportDERPrivateKeyInfoAndReturnKey(slot, &der, NULL, NULL, PR_FALSE, PR_TRUE, KU_ALL, &pkey, NULL);
  	SECITEM_FreeItem(&der, PR_FALSE);
  	if (s != SECSuccess) goto looser;
  	if (!pkey) goto looser;
  	if (pkey->keyType != rsaKey) goto looser;
  	s = SEC_SignData(&signature, (unsigned char*) m, strlen(m), pkey, SEC_OID_ISO_SHA1_WITH_RSA_SIGNATURE);
  	if (s != SECSuccess) goto looser;
  
  	rv=oauth_encode_base64(signature.len, signature.data);
  	SECITEM_FreeItem(&signature, PR_FALSE);
  
  looser:
  	if (pkey) SECKEY_DestroyPrivateKey(pkey);
  	if (slot) PK11_FreeSlot(slot);
  	xfree(key);
  	return rv;
  }
  
  int oauth_verify_rsa_sha1 (const char *m, const char *c, const char *sig) {
  	PK11SlotInfo      *slot = NULL;
  	SECKEYPublicKey   *pkey = NULL;
  	CERTCertificate   *cert = NULL;
  	SECItem            signature;
  	SECStatus          s;
  	SECItem            der;
  	int                rv=0;
  
  	char *key = oauth_strip_pkcs(c, NS_CERT_HEADER, NS_CERT_TRAILER);
  	if (!key) return 0;
  
  	oauth_init_nss();
  
  	s = ATOB_ConvertAsciiToItem(&signature, (char*) sig); // XXX cast (const char*) -> (char*)
  	if (s != SECSuccess) goto looser;
  	slot = PK11_GetInternalKeySlot();
  	if (!slot) goto looser;
  	s = ATOB_ConvertAsciiToItem(&der, key);
  	if (s != SECSuccess) goto looser;
  	cert = __CERT_DecodeDERCertificate(&der, PR_TRUE, NULL);
  	SECITEM_FreeItem(&der, PR_FALSE);
  	if (!cert) goto looser;
  	pkey = CERT_ExtractPublicKey(cert);
  	if (!pkey) goto looser;
  	if (pkey->keyType != rsaKey) goto looser;
  
  	s = VFY_VerifyData((unsigned char*) m, strlen(m), pkey, &signature, SEC_OID_ISO_SHA1_WITH_RSA_SIGNATURE, NULL);
  	if (s == SECSuccess) rv=1;
  #if 0
  	else if (PR_GetError()!= SEC_ERROR_BAD_SIGNATURE) rv=-1;
  #endif
  
  looser:
  	if (pkey) SECKEY_DestroyPublicKey(pkey);
  	if (slot) PK11_FreeSlot(slot);
  	xfree(key);
  	return rv;
  }
  
  char *oauth_body_hash_file(char *filename) {
  	PK11SlotInfo  *slot = NULL;
  	PK11Context   *context = NULL;
  	unsigned char  digest[20]; // Is there a way to tell how large the output is?
  	unsigned int   len;
  	SECStatus      s;
  	char          *rv=NULL;
  	size_t         bl;
  	unsigned char  fb[BUFSIZ];
  	unsigned char *dgst;
  
  	FILE *F= fopen(filename, "r");
  	if (!F) return NULL;
  
  	oauth_init_nss();
  
  	slot = PK11_GetInternalKeySlot();
  	if (!slot) goto looser;
  	context = PK11_CreateDigestContext(SEC_OID_SHA1);
  	if (!context) goto looser;
  
  	s = PK11_DigestBegin(context);
  	if (s != SECSuccess) goto looser;
  	while (!feof(F) && (bl=fread(fb,sizeof(char),BUFSIZ, F))>0) {
  		s = PK11_DigestOp(context, (unsigned char*) fb, bl);
  		if (s != SECSuccess) goto looser;
  	}
  	s = PK11_DigestFinal(context, digest, &len, sizeof digest);
  	if (s != SECSuccess) goto looser;
  
  	dgst = xmalloc(len*sizeof(char)); // oauth_body_hash_encode frees the digest..
  	memcpy(dgst, digest, len);
  	rv=oauth_body_hash_encode(len, dgst);
  
  looser:
  	fclose(F);
  	if (context) PK11_DestroyContext(context, PR_TRUE);
  	if (slot) PK11_FreeSlot(slot);
  	return rv;
  }
  
  char *oauth_body_hash_data(size_t length, const char *data) {
  	PK11SlotInfo  *slot = NULL;
  	PK11Context   *context = NULL;
  	unsigned char  digest[20]; // Is there a way to tell how large the output is?
  	unsigned int   len;
  	SECStatus      s;
  	char          *rv=NULL;
  
  	oauth_init_nss();
  
  	slot = PK11_GetInternalKeySlot();
  	if (!slot) goto looser;
  	context = PK11_CreateDigestContext(SEC_OID_SHA1);
  	if (!context) goto looser;
  
  	s = PK11_DigestBegin(context);
  	if (s != SECSuccess) goto looser;
  	s = PK11_DigestOp(context, (unsigned char*) data, length);
  	if (s != SECSuccess) goto looser;
  	s = PK11_DigestFinal(context, digest, &len, sizeof digest);
  	if (s != SECSuccess) goto looser;
  
  	unsigned char *dgst = xmalloc(len*sizeof(char)); // oauth_body_hash_encode frees the digest..
  	memcpy(dgst, digest, len);
  	rv=oauth_body_hash_encode(len, dgst);
  
  looser:
  	if (context) PK11_DestroyContext(context, PR_TRUE);
  	if (slot) PK11_FreeSlot(slot);
  	return rv;
  }
  
  #else
  /* use http://www.openssl.org/ for hash/sign */
  
  #ifdef _GNU_SOURCE
  /*
   * In addition, as a special exception, the copyright holders give
   * permission to link the code of portions of this program with the
   * OpenSSL library under certain conditions as described in each
   * individual source file, and distribute linked combinations
   * including the two.
   * You must obey the GNU General Public License in all respects
   * for all of the code used other than OpenSSL.  If you modify
   * file(s) with this exception, you may extend this exception to your
   * version of the file(s), but you are not obligated to do so.  If you
   * do not wish to do so, delete this exception statement from your
   * version.  If you delete this exception statement from all source
   * files in the program, then also delete it here.
   */
  #endif
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include "xmalloc.h"
  #include "oauth.h" // base64 encode fn's.
  #include <openssl/hmac.h>
  
  char *oauth_sign_hmac_sha1 (const char *m, const char *k) {
  	return(oauth_sign_hmac_sha1_raw (m, strlen(m), k, strlen(k)));
  }
  
  char *oauth_sign_hmac_sha1_raw (const char *m, const size_t ml, const char *k, const size_t kl) {
  	unsigned char result[EVP_MAX_MD_SIZE];
  	unsigned int resultlen = 0;
  
  	HMAC(EVP_sha1(), k, kl,
  			(unsigned char*) m, ml,
  			result, &resultlen);
  
  	return(oauth_encode_base64(resultlen, result));
  }
  
  #include <openssl/evp.h>
  #include <openssl/x509.h>
  #include <openssl/x509v3.h>
  #include <openssl/ssl.h>
  
  char *oauth_sign_rsa_sha1 (const char *m, const char *k) {
  	unsigned char *sig = NULL;
  	unsigned char *passphrase = NULL;
  	unsigned int len=0;
  	EVP_MD_CTX md_ctx;
  
  	EVP_PKEY *pkey;
  	BIO *in;
  	in = BIO_new_mem_buf((unsigned char*) k, strlen(k));
  	pkey = PEM_read_bio_PrivateKey(in, NULL, 0, passphrase); // generate sign
  	BIO_free(in);
  
  	if (pkey == NULL) {
  		//fprintf(stderr, "liboauth/OpenSSL: can not read private key\n");
  		return xstrdup("liboauth/OpenSSL: can not read private key");
  	}
  
  	len = EVP_PKEY_size(pkey);
  	sig = (unsigned char*)xmalloc((len+1)*sizeof(char));
  
  	EVP_SignInit(&md_ctx, EVP_sha1());
  	EVP_SignUpdate(&md_ctx, m, strlen(m));
  	if (EVP_SignFinal (&md_ctx, sig, &len, pkey)) {
  		char *tmp;
  		sig[len] = '\0';
  		tmp = oauth_encode_base64(len,sig);
  		OPENSSL_free(sig);
  		EVP_PKEY_free(pkey);
  		return tmp;
  	}
  	return xstrdup("liboauth/OpenSSL: rsa-sha1 signing failed");
  }
  
  int oauth_verify_rsa_sha1 (const char *m, const char *c, const char *s) {
  	EVP_MD_CTX md_ctx;
  	EVP_PKEY *pkey;
  	BIO *in;
  	X509 *cert = NULL;
  	unsigned char *b64d;
  	int slen, err;
  
  	in = BIO_new_mem_buf((unsigned char*)c, strlen(c));
  	cert = PEM_read_bio_X509(in, NULL, 0, NULL);
  	if (cert)  {
  		pkey = (EVP_PKEY *) X509_get_pubkey(cert);
  		X509_free(cert);
  	} else {
  		pkey = PEM_read_bio_PUBKEY(in, NULL, 0, NULL);
  	}
  	BIO_free(in);
  	if (pkey == NULL) {
  		//fprintf(stderr, "could not read cert/pubkey.\n");
  		return -2;
  	}
  
  	b64d= (unsigned char*) xmalloc(sizeof(char)*strlen(s));
  	slen = oauth_decode_base64(b64d, s);
  
  	EVP_VerifyInit(&md_ctx, EVP_sha1());
  	EVP_VerifyUpdate(&md_ctx, m, strlen(m));
  	err = EVP_VerifyFinal(&md_ctx, b64d, slen, pkey);
  	EVP_MD_CTX_cleanup(&md_ctx);
  	EVP_PKEY_free(pkey);
  	xfree(b64d);
  	return (err);
  }
  
  
  /**
   * http://oauth.googlecode.com/svn/spec/ext/body_hash/1.0/oauth-bodyhash.html
   */
  char *oauth_body_hash_file(char *filename) {
  	unsigned char fb[BUFSIZ];
  	EVP_MD_CTX ctx;
  	size_t len=0;
  	unsigned char *md;
  	FILE *F= fopen(filename, "r");
  	if (!F) return NULL;
  
  	EVP_MD_CTX_init(&ctx);
  	EVP_DigestInit(&ctx,EVP_sha1());
  	while (!feof(F) && (len=fread(fb,sizeof(char),BUFSIZ, F))>0) {
  		EVP_DigestUpdate(&ctx, fb, len);
  	}
  	fclose(F);
  	len=0;
  	md=(unsigned char*) xcalloc(EVP_MD_size(EVP_sha1()),sizeof(unsigned char));
  	EVP_DigestFinal(&ctx, md,(unsigned int*) &len);
  	EVP_MD_CTX_cleanup(&ctx);
  	return oauth_body_hash_encode(len, md);
  }
  
  char *oauth_body_hash_data(size_t length, const char *data) {
  	EVP_MD_CTX ctx;
  	size_t len=0;
  	unsigned char *md;
  	md=(unsigned char*) xcalloc(EVP_MD_size(EVP_sha1()),sizeof(unsigned char));
  	EVP_MD_CTX_init(&ctx);
  	EVP_DigestInit(&ctx,EVP_sha1());
  	EVP_DigestUpdate(&ctx, data, length);
  	EVP_DigestFinal(&ctx, md,(unsigned int*) &len);
  	EVP_MD_CTX_cleanup(&ctx);
  	return oauth_body_hash_encode(len, md);
  }
  
  #endif
  
  // vi: sts=2 sw=2 ts=2
  